The present invention relates generally to electrical switches and more particularly, to electrical control popout actuator mechanisms.
Currently, many products use controls that extend for easy use and retract for protection and appearance. This trend can be seen in several electronic applications that allow the user to adjust various settings. For example, a typical radio has adjustable volume, tuning, bass, treble and fade. Through the use of popout actuator mechanisms, these electronic applications can be made more aesthetically pleasing to the end customer.
Present electrical popout mechanisms are typically horizontally mounted. This means that the control is mounted to a separate piece of breakaway printed circuit board (PCB) which runs parallel to the centerline of the control. The electrical connection for the system integration of these controls is accomplished with connectors and a wiring harness or flat ribbon cable.
The principle disadvantage of present horizontally mounted popout controls is its large number of parts. The material cost of a horizontally mounted popout control is relatively high due to the PCB, mounting hardware, connectors, and wiring harness. These several parts also take up valuable space that could be used for other features or to reduce total package size. Manufacturability and reliability are also affected by the complexity of present electrical popout control mechanism and systems. The extra connections between the two PCBs create opportunities for electrical problems that could result in product failure, and a decrease in accuracy and reliability.
The complexity of horizontally mounted popout control mechanisms also increases assembly and manufacturing costs. Considerable design and assembly efforts are required to incorporate existing popout controls into a product due to the difficulties of component alignment.
In an effort to overcome the disadvantages of horizontally mounted popout control mechanisms, some attention has been directed to vertical mount mechanisms. This technology, however, has shortcomings as well. The cam profiles of the current vertical mount technology face each other and are in contact when the shaft member is rotated. This results in unnecessary cam profile wear and in decreased product life. Also, the spring member is mounted on the outside of the shaft member, which makes it subject to contamination. Finally, the shaft members of vertically mounted popout controls often have excessive wobble making them difficult to align.
It is, therefore, an object of the invention to provide an improved electrical popout control mechanism and system. Another object is to provide an electrical popout control mechanism and system having reduced cost and complexity as compared to present popout controls. A further object of the invention is to improve the package space needed for popout control mechanisms.
In one aspect of the invention, an electrical control popout actuator mechanism is integrated with a trimmer potentiometer and vertically mounted directly to a printed circuit board. The electrical control popout actuator mechanism is made up of four major parts: a cam cylinder member, a spring member, a shaft member, and a follower member. Together, these parts allow the electrical control popout actuator mechanism to extend during use and retract when not in use.
The cam cylinder member is integrated with, and used to turn, the trimmer potentiometer. The cam cylinder member is a hollow tube in which the shaft member and follower member resides. The cam cylinder member has one or more shaft member flange slots for keying the shaft member, and an outer cam path for rotating the follower member. The spring member encircles and is attached to the outside of the cam cylinder member. The spring member is used to apply force to one or more flanges on the shaft member and to the end of the cam cylinder member.
The shaft member has a cylindrical shape and is located in the cam cylinder member. One or more shaft member flanges are utilized to key the shaft member to the cam cylinder member. The shaft member flanges extend through the cam cylinder member and engage the spring member. The shaft member also contains an inner cam path for rotating the follower member in conjunction with the outer cam path.
The follower member is mounted to the shaft member such that it can rotate freely about the axis of the shaft member. The follower member also has one or more follower member flanges that are engaged by the inner and outer cam paths such that the follower member is rotated by the cam paths when the shaft member is moved.
The present invention thus achieves an electrical control popout actuator mechanism with fewer parts then conventional technology. The present invention is advantageous in that it reduces the overall cost while improving reliability and packaging space. Further advantages are reduced assembly complexity and improved actuator alignment.
Additional advantages and features of the present invention will become apparent from the description that follows, and may be realized by means of the instrumentalities and combinations particularly pointed out in the appended claims, taken in conjunction with the accompanying drawings.